128 DISEASES OF THE SWEET PEA 



after this function has been performed it is 

 quite probable that the male worm takes 

 no more food. 



Omnivorous Nature of the Eel 

 Worm. Root knot injury is not confined 

 to sweet peas alone. There are two hun- 

 dred and thirty-five species of plants 

 known to suffer from it. This number in- 

 cludes all the important families of flow- 

 ering plants, gymnosperms, and ferns. Of 

 the greenhouse plants practically all are 

 subject to root knot. Violets, carnations, 

 chrysanthemums, tomatoes, cucumber^ 

 and lettuce are often ruined by this pest. 



Among the plants which are not affected 

 by eel worm are the following : crab grass, 

 red top, Johnson grass, rye, corn, perennial 

 rye grass, timothy, and Zinnia. For the 

 purposes of greenhouse rotation none of the 

 foregoing plants is of any value. Should 

 root knot attack sweet peas outdoors, how- 



